Systems and apparatus for continuously effecting gas-liquid reactions have traditionally favored countercurrent flow of the reactant streams of gas and liquid. Notable long standing examples of this dominant trend include the prevailing practice in operating equipment such as packed columns, bubble-tray columns, spray towers and the like.
A rare example of the continuous production of a fluid chemical reagent by reacting a gas with a liquid in a steady state cocurrent flow system is recorded in U.S. Pat. Nos. 2,889,199 and 2,965,443 of Osborne et al, wherein chlorine gas is reacted with an aqueous slurry of calcium hydroxide to produce a calcium hypochlorite bleach solution. However, the reactor employed in these patents consists of nothing more than an extended length or loop of ordinary piping (Reference numeral 16 in drawings). Other patents directed to gas-liquid mixing for purposes of treating said liquid also disclose cocurrent flow apparatus and systems such as U.S. Pat. No. 2,606,150 to Thorp and U.S. Pat. No. 3,997,631 of Matsuoka et al. These patents feature the use of liquid jet eductors or ejectors to mix ozone gas into the liquid being treated, e.g. water. Similar ejectors have also been employed in various systems and apparatuses for effecting gas-liquid reactions, e.g. in U.S. Pat. Nos. 4,483,826 (Louthan); 1,808,956 (Ketterer); 2,020,850 (Myhren et al); and 2,127,571 (Pardee, Jr.). However, U.S. Pat. Nos. 4,483,826 and 1,808,956 are directed only to batch or semi-batch operations, while the continuous reaction systems taught by U.S. Pat. Nos. 2,020,850 and 2,127,571 rely upon a counter current overall flow pattern between the gas and the liquid reactants in spite of the localized cocurrent flows which occur in the ejector units shown in said patents. Moreover, the apparatuses and systems of the latter two references are unduly complex, expensive and cumbersome to operate since they both involve a repetitive multiplicity of all the various pieces of equipment utilized therein, notably the ejectors, pumps, valves, separators, etc.